president obama vows to take action against guns and a culture of violence and faces some tough questions from one of our own. >> this is not the first issue, the first incident of horrific gun violence of your four years. where have you been? >>> from the global resources of abc news, with cynthia mcfadden and bill weir in new york city, and terry moran in washington, this is a special edition of "nightline" -- tragedy at sandy hook, the search for solutions. >>> good evening. i'm terry moran. today the shattered community of newtown, connecticut, mourned the young teacher who died trying to protect her first grade class, while school districts across the country are now beefing up security. in the wake of this tragedy, schools nationwide are grappling with the difficult questions about keeping their students safe, including the debate over arming teachers with guns. here's alex perez. >> reporter: she came face to face with unthinkable horror and fought to save her first graders. laid to rest today, 27-year-old sandy hook teacher vicki soto. those remembers her we're green ribb ribbons,